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HIntersection, HIntersectionList
Syntax
HIntersection(I_1:IDEAL,...,I_n:IDEAL):IDEAL
HIntersectionList(L:LIST of IDEAL):IDEAL
Summary
intersection of ideals
Description
The function HIntersection
returns the intersection of I_1,...,I_n
using a Hilbert-driven algorithm. It differs from Intersection
only
when the input is inhomogeneous, in which case, HIntersection
may be faster.
The function HIntersectionList
applies the function HIntersection
to the elements of a list, i.e., HIntersectionList([I_1,...,I_n])
is
the same as HIntersection(I_1,...,I_n)
.
The coefficient ring must be a field.
example
Use R ::= Q[x,y,z];
HIntersection(Ideal(x-z,y-2z),Ideal(x-2z,y-z));
Ideal(x + y - 3z, y^2 - 3yz + 2z^2)
-------------------------------
L := [Ideal(x-z,y-2z),Ideal(x-2z,y-z)];
HIntersectionList(L);
Ideal(x + y - 3z, y^2 - 3yz + 2z^2)
-------------------------------
See Also